When the Taxable by other Formulas setting is enabled, the tax amount itself may be taxed by another Tax Formula.
In a few places (i.e., parts of Canada), some taxes are themselves taxable. The Taxable by other Formulas setting makes the tax in the Tax Subtotal available to be used to figure taxes for other Tax Formulas.
Note: Taxable by other Formulas should normally be disabled unless a local taxing authority assesses a tax on taxes imposed by other districts.
Tax Tables - General Information
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